I posted this thread in the board "Desktop", I think it more appropriate to post here, So I do again here.

I am running xfce4 on my laptop. the graphic card is ATi HD Radeon mobility 4570. I heard that ati open sourced drivers doesn't have power manager, so it will be unpleasant when it is unplugged with AC adaptor. That's why I chose fglrx and have been using this until now. All go very well.

Today, I got some news. From catalyst 12.6, my card won't be supported by fglrx. The bottom line is Radeon 5xxx. In addition, I am trying to use cairo-dock with opengl, but it sucks. I've confirmed that it is due to the graphic card, either the hardware, the drivers or cairo-dock's code for this part,. So I start thinking of moving to use the open sourced driver. But I still have some questions.

First one and of course the important one is whether the open sourced drivers have improved the power manager. Does it do well in economizing the power when I use battery?

Heard of weak performance if we compare it with the fglrx drivers, but is the gap so big? For the record, I don't use software with high demand for graphics card. But I always watch HD videos, 720p even 1080p.